package Test;

public class Demo06 {
    public static void main(String[] args) {
         int[] arr = new int[20];
         arr[0]=1;
         arr[1]=1;
        for (int i = 2; i < arr.length; i++) {

            arr[i]=arr[i-1]+arr[i-2];
        }
        System.out.println(arr[19]);
    }
}
